1. Technical Field
The present invention is directed toward a window operator, and more particularly toward an operator for opening and closing an awning type window.
2. Background Art
Manually operable window operators for casement and awning type windows are well known in the art.
In casement type windows, a window and sash are mounted for pivoting about one of the vertical sides, and the operator connects to an adjacent side for pivoting the sash for opening and closing. A variety of operators usable with casement type windows are shown, for example, in commonly owned Van Klompenburg et al. U.S. Pat. No. 4,241,541, Peterson et al. U.S. Pat. No. 4,253,276, Erdman et al. U.S. Pat. No. 4,266,371, Nelson U.S. Pat. No. 4,305,228, Allen U.S. Pat. No. 4,823,508, Tucker U.S. Pat. No. 4,840,075, and Nolte et al. U.S. Pat. Nos. 4,843,703 and 4,845,830.
With awning type windows, the window and sash are mounted for pivoting about one of the horizontal sides (generally the top side), and the operator connects to the opposite side to control opening and closing of the sash. An operator usable with awning type windows is shown, for example, in my commonly owned U.S. Pat. No. 4,617,758.
Naturally, operators for the different types of windows have some common features. For example, with either type window, it is typically for the operator to have a mounting base which rotatably mounts a gear and pull arm. The gear meshes with a worm gear on a worm shaft having a handle affixed thereto and a pull arm is operatively connected to a window whereby rotation of the worm shaft results in rotation of the gear and the pull arm for window movement.
Nevertheless, it is well understood by those having skill in the art that operators for awning type windows not only operate differently than operators for casement type windows (due to the different movement of the sash relative to the operator base), but they encounter and must be able to withstand distinctly different forces and stresses during operation. For example, motion of the bottom portion of the pivoting sash of an awning type window is both out and up relative to the frame; there is no lateral (sideways) motion. Accordingly, it is desirable to minimize any lateral forces introduced to the sash by the operator, since such forces are counter-productive, can unnecessarily stress and therefore damage the hinges at the top of the sash, can cause the sash to not provide a proper weather seal, and can even prevent the operator from properly working.
Of course, it is also more generally desirable for any such operator to be easily and inexpensively manufactured and installed. It is still further desirable for such operators to provide reliable and smooth operation over the long life of whatever awning type window structure it controls for opening and closing.